In all honesty I don’t have a set answer because there are various pros and cons to using gTLDs (generic top-level domains) and also ccTLDs (country code top-level domains) and it depends on how the website/s are going to be managed and what budgets are available.

Country-code top-level domain names (ccTLDs) give solid signals to both users and search engines that your website is solely intended for a certain country, although unconfirmed it may even have slight ranking benefits. A generic TLD utilising subdirectories such as /uk, /fr, /de etc. for example doesn’t give signals as strong with regards to country targeting. Therefore if this is adopted it’s recommended to add rel="alternate" hreflang="x" tags to the source code of each site to help. For example:

It’s important that the value of the hreflang attribute identifies the language in ISO 639-1format and optionally the region in ISO 3166-1 Alpha 2 format of an alternate URL.

Google states:

Each language page must identify all language versions, including itself. For example, if your site provides content in French, English and Spanish, the Spanish version must include a rel="alternate" hreflang="x" link for itself in addition to links to the French and English versions. Similarly, the English and French versions must each include the same references to the French, English and Spanish versions.

Google also recommends not usingcookies to show translated versions of the page. Instead consider cross-linking each language version of a page, like this:

That way, a user who lands on the wrong version of your page can get to the right language version with a single click.

Automatic redirection of the website from one version to the other based on the user’s perceived language should be avoided because these redirections could prevent users (and search engines) from viewing all the versions of your site.